Why tube amps?

[ajay124]

Now that I have a decent solid state amp (Bryston Pre/Power),I am curious about Tube Amps and how they work and how they sound.I have no intention of switching from the Bryston's as I am extremely happy with them but I would simply like to understand tube's better.At present my Tube amp audition experience is a pleasant day spent at Lyrita where I came away impressed with the sweetness but unconvinced with the accuracy of the sound.I did not pursue it further because the kind of tube amps I may have been happy with...Jadis/Octave/Unison Research/Conrad Johnson seemed out of reach.Also I did not want to buy something which supposedly need extra care/patience/maintenance etc.I would appreciate if all the folks with first hand knowledge and experience of tube amps (Viren most of all) would share what they know with all of us.I don't want to start a solid state v/s tube thread or a bash one or the other kind of thread but simply a thread which increases our understanding of tube amps.
On my first google search I came acroos these You Tube videos.
YouTube - Tube Amps 1: Why Tube Amps?
YouTube - Tube Amps 2: Structure
YouTube - Tube Amps 3: Preamp And Power Tubes
YouTube - Tube Amps 4: The Distortion Chain
YouTube - Tube Amps 5: Volume
YouTube - Tube Amps 6: Attenuators
I have watched the first 3 and this guy does not seem to be very impressed by tube sound.However that's just one man's opinion.I am sure there are many learned guys out there who love tube sound....

 

[hemantwaghe]

I did not pursue it further because the kind of tube amps I may have been happy with...Jadis/Octave/Unison Research/Conrad Johnson seemed out of reach..

So Ajay you want tube amp which is powerful? So why not McIntosh?

 

[iaudio]

Ajay,
Viren, Rajiv, Stevie, Clearcut are a few people who come to mind, who can provide a lot of insight on tube amps.
But i do have the fear that this might turn out to be a tube vs. SS bashing thread.
From my limited exposure, tube amps seem to have these lush, rich mids which can be quite involving for certain types of music. On the theoretical side, from what I have been told, these tube amps have a low damping factor which means that they dont have an iron grip on the cone as certain ss amps do, and because of the same reason the former works best with single driver full range speakers.
But this is all just general, superficial stuff. I will wait for the seniors to pour in their insights.

 

[ajay124]

So Ajay you want tube amp which is powerful? So why not McIntosh?

Hemant,I don't 'want' a Tube Amp rightaway,because at the moment I have neither the knowledge nor the funds to be thinking of buying one.I simply want to understand them better and maybe buy one in the future to sit alongside my Bryston's.

 

[ajay124]

Ajay,
Viren, Rajiv, Stevie, Clearcut are a few people who come to mind, who can provide a lot of insight on tube amps.
But i do have the fear that this might turn out to be a tube vs. SS bashing thread.
From my limited exposure, tube amps seem to have these lush, rich mids which can be quite involving for certain types of music. On the theoretical side, from what I have been told, these tube amps have a low damping factor which means that they dont have an iron grip on the cone as certain ss amps do, and because of the same reason the former works best with single driver full range speakers.
But this is all just general, superficial stuff. I will wait for the seniors to pour in their insights.

I sincerely hope this thread dosen't turn into a ss/tube thing.In fact I would be happy if SS is kept in the background and posters focus mainly on the Tube sound.

 

[hemantwaghe]

McIntosh 2301 is Poer Amp ,Tube based ,300 W RMS ONLY! Featherweight at just 65 Kgs!

McIntosh | MC2301

McIntosh cranks out five expensive new components - SlipperyBrick.com

Price was around 11000 US$ and you need 2 ogf thse for stereo listening!

 

[malvai]

Hi ajay!
Here is my take on the tube amps:
Tube amps are the ultimate evolution for most of us chasing audio nirvana... BUT when I say this I mean only the very high-end tube gear. That's really expensive stuff... That kind of gear gives you all the dynamics, lush mids, airy high's, great bottom end slam etc. But COSTS upto 3-10 times a comparable SS set up...

I find that modern day SS amps do almost everything right at a lesser price.

With tube amps one would also need serious power conditioners... especially in this country of ours where the power is very very unclean. Without clean power one never tastes the real glory of what tube set ups can do.

All in all a very expensive proposition, unless one looks at cheap tube gear. Which brings us back to square one...

 

[sidvee]

My opinion is that tubes bring in a smoothness and lushness that is almost impossible to replicate in all but very expensive solid state set ups. Also my observation has been - after living with tubes for the past 15 years or so - there is an immediacy and intimacy that is created by tubes that I have not felt in any solid state amp. so far. OTOH you loose some bass slam and potentially macro dynamics - especially if the speaker presents a difficult load.
Some of the tube amps. that I used to own in the past:
Cary six pacs
conrad johnson mv55
Antique sound labs monsoon
quicksilver mini mite
I currently own the quicksilver mid monos and have had them for the past 4 years.
Cheers
Sid

 

[stevieboy]

Hi Ajay124,

Well it's a minefield in terms of latent opinions waiting to burst under you hehe. Here's my experience in tubes so far.

1. If you know the signature sound of each tube type you're more likely to then find an amp you'll love for a longer time. Manufacturer comes next. Most people start with a well reviewed amp, without understanding how different tubes sound and that's a mistake they'll come face to face with later on. Also knowing what tube rolling path is open to you after that is very helpful to tweak the sound to your specific ear taste. No matter what the reviews say, there's no way in hell a manufacturer is gonna be able to make an el84 SET or push pull amp sound like an 845/300B/45 amp. So pick your preferred tube first and the amp will follow automatically with a bit of searching.

2. I don't know whether you'd get 'accuracy' the way it translates from a ss point of view, considering the built-in distortion nature of tubes, but quite a few manufacturers strive for 'tonal accuracy'.

3. Maintenance is the biggest myth, either you have auto bias amps which don't require you to do anything or the manufacturer provides bias adjustment which you can do easily every 6 months or year depending on how analytical you want to get. The only thing you need to be careful of is not banging the tube accidentally or touching em while they're hot. In fact tube amps Viren once told me are more tolerant of current fluctuation and less likely to blow up from a surge.

4. Immediacy - I've found nothing comes close to a SET amp for immediacy and emotional connection with the music. To get this, you give up power (unless it's the rarer high powered 845 tube type of SET), you give up the bass control of the push pull amps and speaker choices are narrowed.

Other than that I don't know if most people get into tubes for accuracy. I think, and this is a personal opinion, that the people who love tube sound care more about the music coming alive for them emotionally and there's a lot of intangible 'pulling in' factor involved, rather than details being accurately reproduced. There's some amount of romance involved

From what I've heard so far, the 45 ST tube is the most 'accurate', getting quite to the heart of the music. The 2A3 is more of a romantic lush sound. The 45 globe tubes are infinitely more involving especially in the midrange but lack the bass punch of the 45 ST tubes.

The 845s are powerful but to my ears lack the emotional appeal. They'd probably appeal to someone looking for power, a more linear reproduction.

The el84s are very bluesy to my ears, hard, driving sound.

The el 34s are the fence sitters, doing things well but I just can't remember any good aspect of them. Quite forgettable for me.

Hope this helps!

Regards

Edit: I see sidvee has posted while I was writing and says pretty much the same about the intimacy/immediacy factor. He has listened to far more tube amps than I have, I've heard only what's locally available, but the impressions seem to be the same.

Edit Edit: One other thing I've found is that the sound of individual tubes have been reviewed pretty accurately online, if you junk the extreme opinions and take the average. Eg most guys concur that the Telefunken ecc83s are linear, extended at both ends and neutral/accurate while Mullards are sexy midrange etc etc... Whether you end up liking the sound is a different matter, but once you listen you find yourself describing the sound pretty much the same way you read it online. Individual amp reviews however are a different cup of tea altogether with a lot more subjectivity coming into play.

 

[sidvee]

I think stevieboy summed it up real nicely:thumbsup: including sounds of different tubes. And that IMO is another advantage of tubes wherein you can change tubes - provided the maufacturer allows tube rolling - and get different sound signatures.
Cheers
Sid

 

[gobble]

Just FYI. I was collecting all the tube amp audio manuals lying scattered around my room .. um, the Internet actually and came across this comment from a tube guru of many many decades back.

Basically he said that The world needs to stop thinking about THD or Total Harmonic Distortion as a measure of the degree of unpleasantness that a listener experiences when listening to tube gear.

While most SS gear will have THD in .00x % range, tube gear normally has THD in the 1% range.

I am going the tube way for daily listening - but strictly DIY by hopefully late this year or early next year after I finish reading up my first few books on electronics. And I don't believe I want a SS power rectification either. I am going to research the best design do-able by a beginner for tube rectification and experiment with it. Because I believe the presence of tubes in a PSU have a lot to do with the sound, even though many tube designs with SS rectification give a better pace and speed.

And this conviction about tubes comes from growing up listening to my Grandma's Bush radio. The spoken word with plain news reading or talk shows had a sing-song quality to it with dips and crests following the natural intonation and pitch of the host and announcer with a sense of unparalleled and infinite gracefulness. - yes the word infinite is very very apt here - it put me in deeply in touch with a sense for what infinity is in a non-verbal non-mathematical way, with a spellbinding and a marvelous sense of grace, every time I listened even causally. That sense of Grace is missing in most audiophile SS gear. Period!! (while my 1970s non-audiophile 300 rupee radio had it!!)

You've all heard about portraying musicality when it comes to reproduction of music - Fancy hearing musicality when the intent and source material being reproduced is not music?!! hyeah:


Ultimately I also plan to build a tube based radio tuner, not utilizing any solid state circuitry - with a simple Regenerative Receiver design mimicking the 1930s and 40s.

Tubes all the way!!! Go Tube!! :licklips: :clapping: hyeah:

Solid state is one about convenience and cost ratio beginning with manufacture and the entire consumer goods chain. But Tubes are what humans invented and discovered when they had a deep sense for what is good - before the demands of crass consumerism set itself upon the modern world.

Oh yes, until I find that slam in tube gear, I will continue to have an SS power amp. But once I build my mono tube amp and brand new vintage radio, I expect to switch on my main music system only once a fortnight and forget it even exists for the most part of the week.


Just my Chaar Aanaas as always ...

 

[psychotropic]

one point here. tube amps for guitars and for musical reproduction are two different animals. for guitars, it is all about tone. it is about getting your electric guitar to sound as rich and warm and crunchy and all of those things. There is no 'fidelity' objective at all. you're ALWAYS playing with the tone. you're NEVER trying to hew to a standard of accuracy or transparency or any of those things. you're free to play around and modify and modulate and deviate as much as you want to get that sound that you love. that's what you must do, and tubes give you a whole bunch of interesting options there, and the same even order harmonic distortion is present in guitar tube amps, so they are bestowed with warmth and body and all of those things.....'emotion' even

when it's musical reproduction, fidelity is an objective. the attempt is to recreate, within the limits and constraints, what the original recording sounded like. Here there are two schools of thought. The solid state school places fidelity over other factors, and solid state amps are ceteris paribus more detailed, and produce a cleaner signal than tube amps, with greater frequency extension.

The tube school places warmth and richness and 'emotion' over fidelity (this is a generalisation but it's broadly true). So the tube guys are happy to sacrifice a bit of detail and frequency extension to add that 'special sauce' to their music to make it sound sweeter. Euphonics over fidelity. I've heard tube proponents argue that the euphonic even order harmonic distortion of tube amps is more like 'live sound' than the clean sound of SS amps. I don't quite understand how this would be so.

Of course these things are infinitely variable, i've heard the ayon audio tube amp which is superbly detailed and at the same time warm and full-bodied, while at the same time i've heard the Lyrita SET at thevortex's place which obviously sacrifices some detail, frequency extension and slam to give the sound its body and warmth. And on the other hand there are the NAD SS amps that don't out out the most detailed sound either, while perhaps providing more 'body' than other SS amps.

Anyways, to sum up my rambling point, even someone who uses solid-state for his music reproduction may well much prefer tube amps for his guitar, simply because it's tonal modulation you're aiming for with guitar amps and not accuracy or fidelity.

 

[psychotropic]

oh one more point in favour of the tubes. There are so many limitations and constraints in the chain between live sound that is recorded, stored and then reproduced in a room, that the highest level of fidelity is a lost cause anyways. So then why not sweeten that music with a bit of tubes, if that appeals to your tastes?

 

[gobble]

Another interesting article

IEEE Spectrum: The Cool Sound of Tubes

HTH

 

[ajay124]

Trying to list valve amps available/not available in India:
Ayon Orion/Spirit 2/Leben CS300/600--ARN
Pathos Classic One/Logos--Audio People
Unison Research Unico 100/200--Sound & Vision
Cadence VA 1.0--Cadence
2A3 SET/EL84 SET--Lyrita
Audio Research--Audio Vision?
Cary Audio--J & B Sound?
Quad 2 Classic/QC 24P--Designer Audio?
Jadis/Fatman--Lakozy?
Octave/CJ--Sound of Music?
Cayin?
Prima Luna--None
VTL--None
Hyperion--None
Lamm--None
Mcintosh--None

Rethm has not listed any amps on their website but I believe they too offer valve amps.
Did I miss some brands?I have never followed up with the relevant dealers about what they actually have in stock.
I am sure plenty of folks on the forum would have auditioned some of these.So could they please provide inputs about performance,speakers paired with,models,prices etc.

 

[stevieboy]

I've heard tube proponents argue that the euphonic even order harmonic distortion of tube amps is more like 'live sound' than the clean sound of SS amps. I don't quite understand how this would be so.

Hi Psychotropic,

Two points come to mind, one a guess, one fact.

The guess: Most live shows well at least rock ones are amplified through tube gear giving a characteristic sound and that's sort of reproduced with tube amps. Forget fidelity and all, generally talking bout overall sound signature. Of course this does not take into account non tube amplified sound

The fact: Many sounds in nature have the same distortion characteristic even order harmonics which is why I guess tubes sound more 'easy' and 'natural' on the ears.

regards

 

[square_wave]

From what I have noticed, tube amps cannot be seen in isolation. It is a certain synergy with certain loudspeakers which follow a certain design criteria that creates a certain kind of magic.

In a system which is completely transparent and friendly to tube as swell as solid state, the solidstate will have the edge when it comes to frequency extension, micro/macro dynamics and transparency while the tubes will have a certain seductive character in the midrange.

Most folks who are spiteful of the other camp usually have built their systems around a certain philosophy and vehemently support their camp while turning a blind eye to the other.

For example I had once been to a vinyl fanatics house once. He hates cds. I realized later at his house that he listens to cds on a dvd player while have a state of the art LP playback system. Put in other words, he has never explored digital playback systems at all !

It is more about a certain sound that people are after rather than advantages and disadvantages.

 

[iaudio]

Ajay, Add Cayin, Montille to the list.

 

[keith_correa]

The guess: Most live shows well at least rock ones are amplified through tube gear giving a characteristic sound and that's sort of reproduced with tube amps. Forget fidelity and all, generally talking bout overall sound signature. Of course this does not take into account non tube amplified sound

Well, sort of. The sound of the tube driven individual amps for the strings are then reinforced using microphones, paraphernalia and PA SS amps. :lol:

I guess to put it crudely - with this, the closest to a rock concert in a room=tube buffer and a SS amp Or a hybrid amp.

 

[Asit]

Hi all,

I do not have extensive experience with tube gear in general, in all I have heard about 7-8 tube gear, mostly amps, and I own a tube amp for the last 15-16 months. Before that for more than 20 years I owned only SS electronics. I also do not have any technical knowledge. I only rely on the sound I hear. Basically I am a music-lover and a musician. Hence I may not be qualified in talking about tube gear. Nevertheless I am going to share my own experience.

What I find is that generally with tube gear one has the feeling that the musicians are in my room and performing right there. I am in the front row of seats. On the other hand with SS gear, the performers are a bit away from me, in other words I am seating in the back rows. Yes, there is a particular fluidity about the midrange that one perhaps does not get with entry level and even some more expensive SS. However, with my amp, I also get very accurate highs and lows. For the fast and accurate bass, I had to experiment a bit with power cords, connectors and interconnects. So it seems to me a good implementation of tube amp can produce the whole freq range quite accurately and musically in a very involving way, especially when it is mated with willing and appropriate speakers.

One very important aspect of the tube amps is the output level transformer (one for each channel) for the predominant variety of tube amps we talk about. Tube amps are generally quite heavy because of these transformers. I am given to understand the quality of the sound depends quite a lot on them, and so most of the good manufacturers have in-house facility (or perhaps pay some special attention) for this.

As I see there are two aspects of sound: one is the musical aspects like tonal accuracy and macro/micro dynamics, and the other is peripheral aspects like soundstaging and imaging etc. In my mind, both can be achieved in tube gear. However, my previous SS amp had a similar soundstaging (that is more upfront but not as large) but my current tube amp beats it quite comfortably in tonality. BTW, I have heard class A pure SS amp that have many of the features of a good tube amp.

One crucial aspect of any tube gear can be microphonics. I feel even a superbly built tube gear has to be placed 'properly' so that any mechanical vibration is minimized, otherwise because of the macroscopic size of the tubes, there may be undesirable induced EM effects as tiny bits of noise. One can easily improve on this and improve the focus of the sound by trying isolation and damping. This is in a way also important for also all SS sources because they have some moving parts (like a CDP or a cassette deck), but from my experience it is more important for tube gear. I have tried with some quite primitive methods of placements and they are acceptable to me for the moment. In future I plan to experiment further. Obviously to even appreciate and solve the issue, one needs to have a sufficiently resolving system as a whole (that is including proper sources and speakers).

I have little or no experience in tube rolling. This is an unexplored area that I want to explore some day, because I keep on hearing about the different sounds of different tubes. My amp takes only EL84's and I like them. However, I have read many discussions on the net on tube amps, and people in general are discussing more on the amps than the tubes (my impression can be wrong). For example, I give the following link
Best Valve Amp Between 2000 - 5000? [Archive] - pink fish media
where I find people are discussing more about the amps (this is a discussion I read before I bought my amp and it influenced me to some extent).

BTW, there are also tube amps which do NOT use transformers at the output stage. 'Berning' is a brand that comes to mind. As far as I can remember, I have never seen any discussion on (output)-transformer-less tube amps in this forum. If anybody knows anything about them, in what way they are different than the usual tube amps, I shall be delighted to hear.

Regards